Russian journalists working in Britain have reported receiving online threats after Moscow was accused of orchestrating the attempted poisoning of a former double agent in southern England earlier this month.

British Prime Minister Theresa May said Monday that Russia was “highly likely” to be behind the poisoning of ex-spy Sergei Skripal and his daughter Yulia on March 4. May gave Russia a midnight deadline on Tuesday to explain how a military-grade nerve agent developed by the Soviet Union came to be used in the poisoning of the Skripals in the city of Salisbury.